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Altera_Forum
Honored Contributor
Honored ContributorDRAM and SRAM with Cyclone III
Hello all,
I have some general questions regarding the use of DRAM and SRAM memories with Cyclone III devices. 1) DRAM memory Do I need to connect the DRAM memory chip directly to the dedicated pins (actually DPCLK, CDPLK.. and so as documented in Handbook chapter 6) or can I use any I/Os pins? My understand is if I don't connect the device to the dedicated pins I will have to design my own IP (vhdl controller) to control it. But if I use the dedicated pins I could use the macrocell provided by quartus/altera. Am I correct? 2) SRAM memory Since SRAM memory is easy to control, I can connect it on any others I/Os of the Cyclone III. Is there some SRAM macrocell controller provided by Altera/quartus? Do I need to write it myself? Thank you in advance for any advice Best Regards, -Pierre14 Replies
Altera_Forum--- Quote Start --- Thank you for your quick help. I continue to investigate to check if can use any I/Os or if I must use the dedicated pins. If someone has already designed a digital board with Cyclone (II or III whatever) using a DRAM device, please let me know. --- Quote End --- Hello. I did. I connected two DDR SDRAM to CYCLONE III (EP3C25) and everything is working. I don't use altmemphy because I need burst length equal to 8 and altmemphy doesn't support it.- Altera_Forum
Thank you for your quick help. I continue to investigate to check if can use any I/Os or if I must use the dedicated pins.
If someone has already designed a digital board with Cyclone (II or III whatever) using a DRAM device, please let me know. - Altera_Forum
If you are using SOPC Builder, it might provide the kind of SRAM interface you need.
- Altera_Forum
If the DRAM is DDR or DDR2, use the altmemphy megafunction even if you choose not to use the DDR/DDR2 SDRAM High Performance Controller MegaCore for the controller logic. If you do use the MegaCore, it will set up altmemphy automatically.
Even if you create the datapath yourself instead of using altmemphy, you should use the recommended pins for DQ and DQS. But it is strongly recommended that you use the free altmemphy if you are using a memory type supported by that megafunction. I don't know anything about the particular pins you mentioned (and I didn't try to look it up).
